The present disclosure is related generally to the field of orthodontics. More particularly, the present disclosure is related to a dental model system which can be manipulated to model a series of tooth configurations for a single patient throughout orthodontic treatment.
Many orthodontic treatments involve repositioning misaligned teeth and changing bite configurations for improved cosmetic appearance and dental function. Repositioning can be accomplished, for example, by applying controlled forces to one or more teeth over a period of time.
Some orthodontic processes use positioning appliances for realigning teeth. Such appliances may utilize a thin shell of material having resilient properties, referred to as an “aligner” that generally conforms to a patient's teeth but is slightly out of alignment with the initial tooth configuration.
Placement of such an appliance over the teeth provides controlled forces in specific locations to gradually move the teeth into a new configuration. Repetition of this process with successive appliances that provide progressive configurations eventually move the teeth through a series of intermediate arrangements to a final desired arrangement. An example of such a system is described in U.S. Pat. No. 5,975,893.
Such systems generally rely on designing and fabricating some, most, or all of the appliances, to be worn by the patient, at the outset of treatment. In some processes the design of the appliances relies on computer modeling of a series of successive tooth arrangements and the individual appliances are designed to be worn over the teeth and to reposition the teeth by using the appliances in a serial order, progressing from a first appliance, through each of the intermediate appliances, to the last appliance.
The set of appliances that is designed and fabricated at the outset of the treatment is typically planned to reposition the teeth to a final desired arrangement. In some cases, the treatment deviates from the planned process. Such deviations can arise from for example, poor patient compliance, or other factors.
The deviations will usually become apparent when the next appliance to be worn in the set of successive appliances does not fit as expected or upon a checkup by the orthodontist where the orthodontist notices that progress is not being made as planned. When a subsequent appliance has a poor fit, it indicates that the tooth arrangement has not progressed to the desired intermediate stage and that the teeth are not ready for the next appliance.
When such deviations occur, the response has usually been to restart the alignment process by creating new appliances based upon the current positioning of the teeth. In order to accomplish this, the location of the teeth has to be re-established and another set of appliances are then planned and fabricated to bring the teeth from the current intermediate arrangement to the desired final arrangement, which is usually the same, or close to the same, as the final arrangement that was the target of the original set of appliances.
Restarting the process, however, can be inefficient and wasteful. For example, in such instances, a number of additional appliances have to be fashioned in order to start the process again at a new (intermediate) starting point. Additionally, the remaining appliances from the original set will usually be discarded, since the treatment plan has been substantially redone, in many instances.